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/*
* This file is part of the Echo Web Application Framework (hereinafter "Echo").
* Copyright (C) 2002-2009 NextApp, Inc.
*
* Version: MPL 1.1/GPL 2.0/LGPL 2.1
*
* The contents of this file are subject to the Mozilla Public License Version
* 1.1 (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
* http://www.mozilla.org/MPL/
*
* Software distributed under the License is distributed on an "AS IS" basis,
* WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
* for the specific language governing rights and limitations under the
* License.
*
* Alternatively, the contents of this file may be used under the terms of
* either the GNU General Public License Version 2 or later (the "GPL"), or
* the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
* in which case the provisions of the GPL or the LGPL are applicable instead
* of those above. If you wish to allow use of your version of this file only
* under the terms of either the GPL or the LGPL, and not to allow others to
* use your version of this file under the terms of the MPL, indicate your
* decision by deleting the provisions above and replace them with the notice
* and other provisions required by the GPL or the LGPL. If you do not delete
* the provisions above, a recipient may use your version of this file under
* the terms of any one of the MPL, the GPL or the LGPL.
*/
package nextapp.echo2.webrender;
import java.io.Serializable;
import javax.servlet.http.HttpSession;
import javax.servlet.http.HttpSessionActivationListener;
import javax.servlet.http.HttpSessionBindingEvent;
import javax.servlet.http.HttpSessionBindingListener;
import javax.servlet.http.HttpSessionEvent;
/**
* An abstract base class representing a single user-instance of an application
* hosted in an application container.
*/
public abstract class UserInstance
implements HttpSessionActivationListener, HttpSessionBindingListener, Serializable {
public static final String PROPERTY_CLIENT_CONFIGURATION = "clientConfiguration";
public static final String PROPERTY_SERVER_DELAY_MESSAGE = "serverDelayMessage";
/**
* The default character encoding in which responses should be rendered.
*/
private String characterEncoding = "UTF-8";
/**
* ClientConfiguration information containing
* application-specific client behavior settings.
*/
private ClientConfiguration clientConfiguration;
/**
* The ServerDelayMessage displayed during
* client/server-interactions.
*/
private ServerDelayMessage serverDelayMessage;
/**
* A ClientProperties object describing the web browser
* client.
*/
private ClientProperties clientProperties;
/**
* The URI of the servlet.
*/
private String servletUri;
/**
* Reference to the HttpSession in which this
* UserInstance is stored.
*/
private transient HttpSession session;
/**
* Provides information about updated UserInstance properties.
*/
private UserInstanceUpdateManager updateManager;
/**
* The current transactionId. Used to ensure incoming ClientMessages reflect
* changes made by user against current server-side state of user interface.
* This is used to eliminate issues that could be encountered with two
* browser windows pointing at the same application instance.
*/
private long transactionId = 0;
/**
* Creates a new UserInstance.
*
* @param conn the client/server Connection for which the
* instance is being instantiated
*/
public UserInstance(Connection conn) {
super();
updateManager = new UserInstanceUpdateManager();
conn.initUserInstance(this);
}
/**
* Returns the default character encoding in which responses should be
* rendered.
*
* @return the default character encoding in which responses should be
* rendered
*/
public String getCharacterEncoding() {
return characterEncoding;
}
/**the ServerDelayMessage displayed during
* client/server-interactions.
* Retrieves the ClientConfiguration information containing
* application-specific client behavior settings.
*
* @return the relevant ClientProperties
*/
public ClientConfiguration getClientConfiguration() {
return clientConfiguration;
}
/**
* Retrieves the ClientProperties object providing
* information about the client of this instance.
*
* @return the relevant ClientProperties
*/
public ClientProperties getClientProperties() {
return clientProperties;
}
/**
* Returns the current transaction id.
*
* @return the current transaction id
*/
public long getCurrentTransactionId() {
return transactionId;
}
/**
* Increments the current transaction id and returns it.
*
* @return the current transaction id, after an increment
*/
public long getNextTransactionId() {
++transactionId;
return transactionId;
}
/**
* Retrieves the ServerDelayMessage displayed during
* client/server-interactions.
*
* @return the ServerDelayMessage
*/
public ServerDelayMessage getServerDelayMessage() {
return serverDelayMessage;
}
/**
* Determines the URI to invoke the specified Service.
*
* @param service the Service
* @return the URI
*/
public String getServiceUri(Service service) {
return servletUri + "?serviceId=" + service.getId();
}
/**
* Determines the URI to invoke the specified Service with
* additional request parameters. The additional parameters are provided by
* way of the parameterNames and parameterValues
* arrays. The value of a parameter at a specific index in the
* parameterNames array is provided in the
* parameterValues array at the same index. The arrays must
* thus be of equal length. Null values are allowed in the
* parameterValues array, and in such cases only the parameter
* name will be rendered in the returned URI.
*
* @param service the Service
* @param parameterNames the names of the additional URI parameters
* @param parameterValues the values of the additional URI parameters
* @return the URI
*/
public String getServiceUri(Service service, String[] parameterNames, String[] parameterValues) {
StringBuffer out = new StringBuffer(servletUri);
out.append("?serviceId=");
out.append(service.getId());
for (int i = 0; i < parameterNames.length; ++i) {
out.append("&");
out.append(parameterNames[i]);
if (parameterValues[i] != null) {
out.append("=");
out.append(parameterValues[i]);
}
}
return out.toString();
}
/**
* Returns the URI of the servlet managing this UserInstance.
*
* @return the URI
*/
public String getServletUri() {
return servletUri;
}
/**
* Returns the UserInstanceUpdateManager providing information
* about updated UserInstance properties.
*
* @return the UserInstanceUpdateManager
*/
public UserInstanceUpdateManager getUserInstanceUpdateManager() {
return updateManager;
}
/**
* Returns the HttpSession containing this
* UserInstance.
*
* @return the HttpSession
*/
public HttpSession getSession() {
return session;
}
/**
* @see javax.servlet.http.HttpSessionActivationListener#sessionDidActivate(javax.servlet.http.HttpSessionEvent)
*/
public void sessionDidActivate(HttpSessionEvent e) {
session = e.getSession();
}
/**
* @see javax.servlet.http.HttpSessionActivationListener#sessionWillPassivate(javax.servlet.http.HttpSessionEvent)
*/
public void sessionWillPassivate(HttpSessionEvent e) {
session = null;
}
/**
* Sets the ClientConfiguration information containing
* application-specific client behavior settings.
*
* @param clientConfiguration the new ClientConfiguration
*/
public void setClientConfiguration(ClientConfiguration clientConfiguration) {
this.clientConfiguration = clientConfiguration;
updateManager.processPropertyUpdate(PROPERTY_CLIENT_CONFIGURATION);
}
/**
* Stores the ClientProperties object that provides
* information about the client of this instance.
*
* @param clientProperties the relevant ClientProperties
*/
void setClientProperties(ClientProperties clientProperties) {
this.clientProperties = clientProperties;
}
/**
* Sets the ServerDelayMessage displayed during
* client/server-interactions.
*
* @param serverDelayMessage the new ServerDelayMessage
*/
public void setServerDelayMessage(ServerDelayMessage serverDelayMessage) {
this.serverDelayMessage = serverDelayMessage;
updateManager.processPropertyUpdate(PROPERTY_SERVER_DELAY_MESSAGE);
}
/**
* Sets the URI of the servlet managing this UserInstance.
*
* @param servletUri the URI
*/
void setServletUri(String servletUri) {
this.servletUri = servletUri;
}
/**
* Listener implementation of HttpSessionBindingListener.
* Stores reference to session when invoked.
*
* @see javax.servlet.http.HttpSessionBindingListener#valueBound(HttpSessionBindingEvent)
*/
public void valueBound(HttpSessionBindingEvent e) {
session = e.getSession();
}
/**
* Listener implementation of HttpSessionBindingListener.
* Removes reference to session when invoked.
*
* @see javax.servlet.http.HttpSessionBindingListener#valueUnbound(HttpSessionBindingEvent)
*/
public void valueUnbound(HttpSessionBindingEvent e) {
session = null;
}
}